| (19) |
 |
|
(11) |
EP 0 389 144 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
15.01.1992 Bulletin 1992/03 |
| (43) |
Date of publication A2: |
|
26.09.1990 Bulletin 1990/39 |
| (22) |
Date of filing: 07.03.1990 |
|
| (51) |
International Patent Classification (IPC)5: C08L 23/16 |
|
| (84) |
Designated Contracting States: |
|
DE ES FR GB IT NL |
| (30) |
Priority: |
09.03.1989 JP 58433/89
|
| (71) |
Applicant: SUMITOMO CHEMICAL COMPANY, LIMITED |
|
Osaka-shi,
Osaka (JP) |
|
| (72) |
Inventors: |
|
- Yamamoto, Keisaku
Ichihara-shi,
Chiba (JP)
- Yamada, Hideaki
Ichihara-shi,
Chiba (JP)
- Iketani, Kohichi
Ichihara-shi,
Chiba (JP)
|
| (74) |
Representative: Diamond, Bryan Clive (GB) et al |
|
Gee & Co.
Chancery House
Chancery Lane
GB-London WC2A 1QU
GB-London WC2A 1QU (GB) |
|
| |
|
| (54) |
Ethylene-olefin rubbery copolymers and composition thereof for use as sponge rubber |
(57) A rubbery terpolymer is made by copolymerisation of ethylene and an alpha-olefin
(e.g. propylene) at a weight ratio of 73:27 to 40:60, and a diolefin (e.g. ethylidene
norbornene) in a liquid organic reaction medium with a Ziegler catalyst; the amount
of diolefin units is such as to give the terpolymer an iodine value of 10 to 38 and
the copolymer has a Mooney viscosity (Ml₁₊₄121
oC) of 135 to 200.
In 100 parts by weight of the polymer is incorporated 30 - 130 parts of a plasticiser,
e.g. process oil, and a foaming agent, and preferably vulcanising additives and a
filler, and the composition is molded, foamed and crosslinked to make a shaped synthetic
rubber sponge useful as a seal for vehicle bodies and which has good compression
qualities and hysteresis loss.